Strategy: The Bears offense has a different look to it under new coach Marc Trestman, who was known as an offensive innovator in the CFL. The Bears use a vertical passing attack to take advantage of strong-armed quarterback Jay Cutler and dangerous outside wide receivers Brandon Marshall and Alshon Jeffery. They also have a versatile running game that tries to get running back Matt Forte into space. On defense, even with former coach Lovie Smith gone, the Bears still use their Cover Two base defense out of a 4-3 front, though it appears they no longer have the personnel to excel in that scheme. They used a lot of zone coverage in their loss to the Lions.

Personnel: The Bears were banged-up heading into the game and came out of it much worse. Already without franchise defensive tackle Henry Melton, Pro Bowl outside linebacker Lance Briggs and defensive end Shea McClellin, the Bears lost standout cornerback Charles Tillman for the rest of the regular season and Cutler also got knocked out of the game and will not play against the Ravens this weekend. With Briggs out and Brian Urlacher in retirement, the Bears are starting a pair of rookies, Jon Bostic and Khaseem Greene, at linebacker. In the offseason, Chicago rebuilt its offensive line and despite having four new starters — veterans Jermon Bushrod and Matt Slauson and rookies Kyle Long and Jordan Mills — that group is playing better.

What went right: After sitting out one game with a groin injury, Cutler clicked with Marshall early as the Bears scored a touchdown on their opening drive. Marshall and Jeffery both had big games, combining for 253 yards and two touchdowns on 16 receptions. They kept the Lions off balance with misdirection, complementing the vertical passing game with things like pre-snap motion, quick pitches, shovel passes, screens and play-action passes. The defense held Lions quarterback Matt Stafford to just 219 yards on 35 attempts while picking off one pass and tipping several others. Despite losing Cutler late in regulation, the Bears nearly sent the game to overtime.

What went wrong: Cutler threw an interception in the end zone with the game tied late in the second half. The Bears couldn’t run the ball as Forte rushed for just 33 yards on 17 carries and backup Michael Bush got stuffed on one fourth-down running attempt. The defense consistently allowed big gains in the running game, particularly between the tackles, including one 39-yard run that Reggie Bush nearly took to the house. Defensive end Julius Peppers was invisible as the pass rush did not bring down Stafford once — they weren’t even credited with a quarterback hit — and their secondary also let at least one should-have-been interception slip through their hands.

Turning point: The Bears trailed, 14-10, early in the fourth quarter when they intercepted Stafford and returned it to the Lions’ 9-yard line. They would score the go-ahead touchdown twice only to have it be taken off the board. Forte’s touchdown run was nullified by a holding penalty. Three plays later, Jeffery appeared to catch a pass in the end zone, but the touchdown was overturned after a review. The Bears would settle for a field goal, and it cost them later.

X-factor: After Cutler was pulled from the game before Chicago’s final drive, backup quarterback Josh McCown completed six of his nine attempts for 62 yards on a touchdown drive, though the Bears could not convert either of their two chances at a two-point conversion. Still, McCown looked solid. He may not have the elite arm strength of Cutler, but the Bears probably won’t have to tweak their downfield passing attack much with McCown under center this